NASA - National Aeronautics and Space Administration

Cleveland's Powerful Connection with the International Space Station

STS-92, launched from Kennedy Space Center at 7:17 p.m. EDT on Wednesday, October 11, has aboard four types of hardware, all parts of station's electrical power system (EPS), in which an important part. On this mission, the Integrated Truss Structure Z1, an early exterior framework, will be installed. It will contain several pieces of hardware:

The Plasma Contactor, which will serve as a high-tech grounding rod for station. The Hollow Cathod Assembly, which is the major component of the contactor, was designed, developed, built and tested at Glenn.

The truss will also contain dc/dc Converter Units to provide grounding and voltage regulation.

Another set of Remote Power Control Modules like those contained in Unity, the first U.S. module installed on station in December 1998. These multi-channel, high-power circuit breakers will provide switching and protection in case of a short circuit during construction of the ISS as well as during operation of the completed station. Glenn led the early design and development of this device and has performed extensive testing of it in its EPS test bed.

Circuit Isolation Devices, which are manually activated switches providing manual shut-off of high power to enable installation/construction as station is assembled. Glenn designed and built these devices. They will be launched on this mission and will be installed on station assembly flights 4A and 5A scheduled to take place in November and January, respectively.

Glenn is especially looking forward to the launch of STS-97, station assembly flight 4A, scheduled for November 30. The first U.S. photovoltaic module, which will supply station with solar power via solar arrays, batteries and other power system electronics, will be launched on that mission. Glenn has had a significant role in the design and development of the PV module and managing the hardware development for it, including testing, system analysis and participating in the neutral buoyancy testing of the assembly operations for the PV module. Also installed on that mission will be two radiators, which will remove waste heat from station. One of these radiator panels was tested in the Space Power Facility, the world's largest space environment simulation chamber at Glenn's Plum Brook Station in Sandusky, OH.

Glenn is the co-lead for station's electrical power system (EPS) in partnership with Johnson Space Center in Houston, TX. In addition, as EPS co-subsystem manager, Glenn is responsible for the technical design and development of all the individual pieces of the EPS on station.

For further information about Space Shuttle or International Space Station in general, visit

http://spaceflight.nasa.gov

http://www.grc.nasa.gov/WWW/PAO/issgrc.htm

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